Method of and apparatus for reducing materials by heat



July 17. 1928. 1,677,784

W. W. KEMP METHOD OF AND APPARATUS FOR REDUCING MATERIALS BY HEAT Filed Nov. 7, 1921 1 6212502.- Willem wallacallgm Patented July 17,1928.

UNITED STATES I WILLIAM WALLACE KEMP, or BALTIMORE, MARYLAND.

METHOD OF AND APPARATUS FOR REDUCING MATEiIAIaS BY HEAT.

Application filed November 7, 1921. Serial No. 513,442.

The present invention relates to a method of and apparatus for the reduction of solid, liquid or semi-liquid materials, .among which may be mentioned carbonaceous materials, and its purpose is the provision of novel means and an improved method 'for the complete and economical reduction of materials to liberate the volatile constituents and reduce the materials to an inert carbon.

Under present methods, the distillation of materials, among which may be mentioned wood, bone, lignite, peat, and, in fact, any material which is capable of distillation, the practice has been toplace such material in retorts, and, by external firing of those retorts, distill the material, driving off the gaseous elements and reducing thesolids to inert matter. This external firing method requires a very high and destructive heat which tends to break down rapidly the retorts in which the distillation is, carried on so that it is uneconomical in this respect, and, furthermore, in practical operation, this method requires relatively long intervals. be-

tween the successive operations of firing the retort to bring it to proper distilling temperature, cooling it after the operation is complete, and removing the reduced materials.

Under the present method and utilizing the apparatus which will be hereinafter described, and one embodiment of which is illustrated in the drawings accompanying this case, it is roposed to internally fire the retort and sub ect the material to be reduced to a temperature sufficiently high to free the gaseous constituents or impurities and leave the char or charcoal in an-ash free revivified condition in the retort. This internal firing is accomplished in the absence of sufficient air to support combustion, either of the volatile products, or the material under reduction, while, at the same time, the heat generated is sufficiently high to accomplish the result-aimed at, the heat being produced'by the flame of a self-sustaining mixture introduced into the retort. As a result of this method, the distilling of the material is effectively carried out, but since there is insuflicient air in the retort to support combustion, either of the liberated gases, or of the material in the retort, all danger of burning of the material or gases, or explosion of these gases, is eliminated, and a true distilling action takes place.

As stated, in order to effectively accomplish this, I propose to subject the material to be reduced to the flame or the heat of a self-sustained fuel mixture, preferably gaseous, which mixture will sustain combustion 1n the absence of air sufiiciently to reduce the material, but which will not cause any burning of the liberated gases or the material under treatment, since there is not sufficient oxygen in the air of the mixture to support combustion of anything but the gas or fuel portion of the mixture.

In order that the invention may be clearly understood by those skilled in the art, I have shown, in the accompanyin drawings, embodiments of my invention, ut it will be understood that this disclosure is merely illustrative, and in no sense restrictive of the invention, as it may be carried out by the use of other expedients and apparatus.

In the drawings Fig. 1 is a viewv in elevation of a reduction apparatus.

Fig. 2 is a view in section of the apparatus shown in Fig. 1, and

Fig. 3 is a view of an apparatus similar to that shown in Figs. 1 and 2, with certain additions and auxiliary appliances applied thereto.

Referring to the drawings by numbers, like numbers indicating like parts in the several views, indicates the reduction chamber, which may be of any approved form, but-is preferably, as shown, in the form of a cylinder which may be rotated in any suitable manner, and is provided with a suit able filling opening having the door or closure 11. The receptacle 10 may be lined, if desired, with refractory material, as conventionally illustrated, and may be mounted for rotation as may be desired, and any convenient means for driving it may be provided.

At one end of the receptacle 10 is provided a stufling box 12 through which passes an inlet pipe 13 for the fuel, preferably gaseous. At the opposite end of the container 10 is provided a similar stufiing box 14 through which extends the outlet pipe 15 for the volatile products driven off from the material 16, conventionally illustrated, as well as the gases of combustion from the internal firing flame. Preferably the delivery pipe 15 will have an upwardly turned neck 17 within the container 10 to receive the gases rising from the material 16 to the upper part of the chamber.

ioo

The exclusion of air from the container so as to prevent supplying enough oxygen to efl'ect ombustion of the material, or liberated gases, and maintain a true distilling action ensured by providing a closed container, such as the container 10, and by maintaining Within that container a pressure from the inlet pipe 13 through which the self sustainingmixture passes suflicient to prevent the entrance of air under atmospheric pressure through any openings or joints in the container.

Preferably, the container 10 will be made as air tight as practicable, but it will be understood that it need not be absolutely sealed from atmosphere because the action of the internal pressure, above referred to, ensures the exclusion of atmospheric .air from the container.

I accomplish the reduction of the material 16, however,- by internal firing,without any danger of burning of the volatile prodnote, by delivering through the pipe 13 a fuel, which is preferably gaseous, and of a self-sustaining character, so that it will burn in the air-tight container, thejet of burning fuel being conventionally illustrated at 18 in Fig. 2. The fuel delivered through the pipe 13 is a mixture of gas and air so regulated as to proportion that it will burn in a confined space, there being just sufficient air to furnish the oxygen required to support combustion of the fuel, but insufficient to cause ignition and burning of the material 16 or any of the volatile products of the material so that a true distillation is carried on, and the gaseousconstituents, as they are liberated, accumulate in the container 10 and are drawn off through the neck 17 and the delivery pipe 15. '7

The combustible mixture constituting the gaseous fuel supplied through the pipe or burner 13 is thoroughly pre-mixed outside the container and before being admitted to the'burner, and as above noted, the gas and air composing the same are so proportionatcd that the oxygen of the air will-not exceed that required to effect combustion of the gas that is thoroughlymixed with theair. This fuel, in which gas and air are thoroughly pre-mixed outside the container, in contrast to a stratified mixtureof gas and air produced by admixing such elements in a burner or within a container, is herein defined as being of a self-sustaining character.

The self-sustaining mixture may be produced by any suitable means and the drawing therefore contains merely a diagram matic showing thereof. An example of an apparatus adapted to provide a combustible mixture such as employed in practicing the present invention is disclosed in patent of Kemp and Van Horn'No. 1,420,658 dated June 27, 1922.

In operation, the cylinder or retort 10 will receive its load of material which is to be reduced, the jet 18 will be ignited, the door 11 closed, and the retort 10 will then be revolved to agitate the material 16 and bring fresh material into the zone of action of the reducing jet.

In the form of the invention shown in Fig. 3, the cylinder 1.9 will be constructed in the form shown in Figs. 1 and 2, but in order that a continuous feed of material through the retort may be secured, I incline this retort 19, as shown, and at the upper feeding end of the retort 19 I provide a feed hopper 20 passing through a stufling box 21 in the retort, with the jet pipe 22 for the self-sustaining mixture traversing the feed pipe of the hopper 20 as shown. The hopper 20 may, if desired, be provided with a cover and any suitable valved feed trap (not shown) at its upper end so that material may be fed to the hopper and thence to the retort continuously.

At the lower or delivery end of theretort 19 a delivery pipe 23, to receive the reduced inert material, will be provided, this pipe delivering through any suitable receptacle and having cut-offs (not shown) to prevent entrance of any considerable volume of air to the retort from that end. A suitable stufling box 24 will surround the pipe 23, and the gas delivery-pipe 25 having the receiving neck 26 Within the retort 19 will be provided.

With this apparatus a continuous operation may be carried on, it being understood that the internal firing and the reduction of material is the same as described in connection with Figs. 1 and 2, but a continuous operation is effected by proper feeding through the hopper 20 of the material to be reduced, the reduced material passing out through the pipe 23 as the retort is rotated. I have found it preferable, or at least desirable, to deliver the self-sustaining fuel, as conventionally illustrated at 18, under a pressure which will not blow the flame too far from the pipe 13 so that danger of driving the flame into the smothering atmosphere of the container and extinguishing it will be avoided, and it will remain adjacent the point of exit from the'pipe so as to insure proper ignition and burning of the self-sustaining fuel.

vBy this means also any possibility of particles of the material being treated or the gases evolved therefrom being drawn into the stream of fuel prior to its being ignited, is entirely avoided.

Following this method and utilizing apparatus capable of performing it, I am able to reduce material by internal firing very effectively and rapidly, and do away with the somewhat cumbersome methods now in apparatus, there is great economy in the matter of fuel, for the application of the distilling temperature being internal and directly supplled to the material under reduction, there is no loss of heat as in exter-' nal firing. Additionally, the initial cost and the cost of maintenance of apparatus necessary to carry out my method is very much reduced over the cost of apparatus used in external firing methods.

While I have shown a particular apparatus for carrying out my invention and have described particular steps for practicing it, it will be understood that-such variations as are merely the work of the skilled mechanic may still be made without departing from the range of my invention.

I claim:

1. Apparatus for reducing material by heat, comprisinga revoluble container from which air is excluded, a stufling box at one end of said container, a burner pipe delivering a jet of self-sustaining fuel 'interiorly of said container through said stufling box, a-stufling box at the other end of the'container, and a gas pipe passing through said second stuffing box to deliver gas from said container exteriorly thereof.

2. Apparatus for reducing material by heat; comprising an inclined, revoluble container from which air is excluded, a feed hopper at one end of said container to deliver a substantially continuous stream of material thereto; a delivery pipe at the opposite end of said container to deliver the reduced product in a substantially continuous stream from said container; a burner pipe delivering a jet of self-sustaining mixture interiorly of said container at the feeding end thereof; and a gas delivery pipe communicating with said container at t e delivery end thereof to deliver the volatile products exteriorl) of said container.

3. Apparatus for reducing materials by heat, comprising an inclined, revoluble container from which air. is excluded, havin a stufling box ateach end, a feed hopper at t e upper end of said container traversing a stufling box to deliver a substantially con tinuous stream of material thereto, a delivery pipe at the lower end of said con-' tainer traversing a-stufiing box to deliver in cinerated products in a substantial stream from said container, a burner pipe traversing said feed hopper and delivering a jet of self-sustaining mixture interiorly of said container, and a gas delivery pipe traversing the delivery pipe for inclneratedprodnets to deliver the volatile products exteriorly of said container.

4. The method of driving constituents of gas producing material by heat, which consists in enclosing the material in a container; excluding air from said container; subjecting the material to oil the vplatile the heat of a self-sustainin flame produced from a burning combusti le mixture injected into the said container and removing the volatile constituents y from said .container.

5. The herein described process for the distillation of carbonaceous material which consists in forming a. perfectly combustible mixture of uniform composition consisting of gases including oxygen, admitting such mixture to and burning it in an air tight 'retort, and passing the material through the retort and subjecting it to the direct action of the flame, thereby heating the material-to separate the volatile matter from the material through decomposition and prevent ing the ignition or burning of the volatile matter or residue.

6. The herein described process. for the distillation, of carbonaceous material such as lignite, which consists in feeding the carbonaceous material intoan air-tight retort moving the carbonaceous material along in the retort, subjecting the material to the di- #0 H rect' action of a flame produced by burning a previously formed combustible mixture, of uniform composition consisting of. gases inmaterial and the retortlandtoicause the volatile matter to separate from the ma-v terial through decomposition without'igniting or burning such material andthen discharging the. volatile -matter from the. re-' eluding oxygen'within' thereto'rt to heat the o5 tort togther with the products of combustion of the said flame, and separately removing the residue from the retort..-

. An apparatus for the treatment of car? bonaceous material consisting in an air-tight retort, means for passing the carbonaceous material through theretort, a burner adapted to direct a flame upon the-material during its passage through the retort, means to thoroughly mix combustible materials. and a port-er of combustion thoroughly mixed outside the container and so proportioned as not to include oxygen in excess of that re-.

quired to effect oxidation of the combustible v material thereof. while excluding from the container air which 'would supply oxygen suflicient to effect combustion of the mate- ;ial being treated or gases evolved thererom.

ing carbonaceous material which consists in 9.- The herein described method of reducenclosing the material "in a cointainer, agitating the material in the container, and subjecting it to the heat of a burning mixture, injected into the container and composed of,

gas and air thoroughly mixed outside the container and so proportioned as not to include oxygen in excess of that required to eflect combustion of the gas-thereof, while excluding from the container air which would supply oxygen suificient to effect combustion of the material being treated or would supply oxygen suflicient'to effect combustion of the material being treated or gases evolved therefrom. v

11. The herein described method of reducing carbonaceous material which consists in passing the material in a substantially continuous stream through a container, and subjecting the material within the. container to theheat of a burning mixture,. injected into the container and composed of gas and air thoroughly mixed outside the container and so proportioned that the airtherein will not furnish oxygen in excess of that required to effect combustion of the gas thereof, while excluding from the-container airwhich would supply oxygen sufficient to effect combustion of the material being treated or gases evolved therefrom.

12. The herein described method of reducing carbonaceous material which consists in enclosing the material in a container, subjecting it to the heat of a burning mixture, injected into the container and composed of gas and air thoroughly mixed outside the container and so proportioned that the air therein will not furnish oxygen in excess of that required to effect combustion of the gas thereof, while excluding from the container air which would supply oxygen sufficient to efl'ect combustion of the material being treated or gases evolved therefrom, and discharging the volatilized constituents of the material from the container.

13. The herein described process for the treatment of carbonaceous material which consists in introducing the material into a chamber from which air is excluded and subjecting the same to the direct action of a flame produced by burning a previously formed mixture, of uniform composition, consisting of combustible material and a 1;' i al, and a supporter of combustion, the I amount of the latter not exceeding that required to effect combustion of the combustible material, introducing the carbonaceous material into a retortfro'm which air is excluded, and burning said combustible mixture in said retort so as to subject the retort and the carbonaceous material to the direct action of the flame and thereby deprive the material of its moisture and decompose it to separate the volatile matter therein from the residue.

15. The herein described process for the treatment of carbonaceous material which consists in forming a mixture, of uniform composition, consisting of combustible material and a sup orter of combustion, the proportion of the atter not exceeding thatre quired to effect combustion of the combustible material, burning thls mixture in a retort, from which air is excluded, and passing carbonaceous material through the retort and subjecting it during its travel to the action of the heated retort and the direct action of the flame resulting from burning the combustible mixture.

16. The herein described process for the treatment of carbonaceous material which consists in forming a mixture, of uniform composition, consisting of combustible material and a supporter of combustion, the amount of the latter not exceeding that. requlred to efiect combustion of the combustible material, burning such mixture in a retort from which air is excluded, passing carbonaceous material through the retort and subjecting it during its travel to the action of the heated retort and the direct action of the flame obtained by burning the combustible mixture, and then separating the volatile matter from ,the residue of the carbonaceous material.

17. The herein described process for the distillation of carbonaceous material such as lignite, which consists in feeding the carbonaceous material into a retort from which air is excluded, moving such material along in the retort, subjecting the material in the retort to the direct action of a flame produced by burning within the retort a previously formed combustible mixture of uniform composition, consisting of gases including oxygen, the amount of oxygen not exiao ceeding that required'to efiect combustion of the mixture, to heat the carbonaceous ma terial and the retort and cause the volatile matter to separate from, the carbonaceous material through decomposition without igniting or burning such material, discharginjected into the retort and comprising a supporter of combustion not exceeding that required to efl'ect combustion of the mixture, and maintaining the flame of such mixture at the point of its admission to the retort whereby particles of the material being treated and gas evolved therefrom are prevented from entering said mixture at points between said point of admission and that at which combustion of the mixture starts and combustion of such material and gas evolved therefrom is prevented.

In testimony whereof I have hereunto set my hand.

WILLIAM WALLACE KEMP. 

